A system for mounting a tailgate attaches the tailgate on a side of a roof panel of a vehicle body through a loading robot using an external mounting jig including an X-direction regulation arm and a Y-direction regulation arm. Then, the system automatically bolts a nut to a hinge of the loaded tailgate through an automatic hinge-nutting robot, thereby finishing an assembling work.
However, according to a conventional system for mounting a tailgate, since an external mounting jig is used, the loading position of the tailgate may not be accurate. Accordingly, since the tailgate is not accurately mounted on a predetermined position, the mounting quality may be degraded.
In addition, since the external mounting jig is used, history of the mounting quality may not be managed, which may be disadvantageous to quality management. Further, since the number of units to be attached to the mounting jig is limited due to the constraint of a mounting space, tailgates of various vehicles may not be compatibly mounted. Therefore, when a new model of a vehicle is additionally produced, additional facility investment costs may be required.